Lens arrangements are known comprising input and output macrolenses or macrolens arrays with intermediate so-called double-integral transmission microlens screens. In all of these arrangements, the input macrolenses cast an image on to the microlens screen arrangement which transmits rays to the output lenses for reconstitution as a pseudoscopic image that can be captured via a decoding screen on to a sensitised screen such as a photographic plate or film or an electronic arrangement such as a charge coupled device (CCD) screen.
In order to cast an image on to the screen, the input array lenses are, of course, positive, or convex lenses, and the output lenses are, naturally, similar.
The input and output lenses must be spaced about the equivalent of their focal lengths from the central microlens screen, which makes the arrangement somewhat more than two focal lengths long.
Problems arise with such lens arrangements that require more or less expensive measures for their solution or alleviation. One such problem is that the input lenses cast an image of the microlens screen as well as of the image cast on that screen, and graininess in the final images is dependent upon the pitch of the microlens screen. Fine pitch screens are clearly desirable, but correspondingly expensive.